The Effect of Moisture Content and Temperature on the Specific Heat Capacity of Nut and Kernel of Two Iranian Pistachio Varieties

Pistachio has a special ranking among Iranian agricultural products. Iran is known as the largest producer and exporter of pistachio in the world. Agricultural products are imposed under different thermal treatments during storage and processing. Designing all these processes requires thermal parameters of the products such as specific heat capacity. Regarding the importance of pistachio processing as an exportable product, in this study the specific heat capacity of nut and kernel of two varieties of Iranian pistachio (Kalle-Ghochi and Badami) were investigated at four levels of moisture content (initial moisture content (5%), 15%, 25% and 40% w.b.) and three levels of temperature (40, 50 and 60°C). In both varieties, the differences between the data were significant at the 1% of probability; however, the effect of moisture content was greater than that of temperature. The results indicated that the specific heat capacity of both nuts and kernels increase logarithmically with increase of moisture content and also increase linearly with increase of temperature. This parameter has altered for nut and kernel of Kalle-Ghochi and Badami varieties within the range of 1.039-2.936 kJ kg-1 K-1, 1.236-3.320 kJ kg-1 K-1, 0.887-2.773 kJ kg-1 K-1 and 0.811-2.914 kJ kg-1 K-1, respectively. Moreover, for any given level of temperature, the specific heat capacity of kernels was higher than that of nuts. Finally, regression models with high R2 values were developed to predict the specific heat capacity of pistachio varieties as a function of moisture content and temperatur

Demarcation and Estimation of Agricultural Lands Using ETM+ Imagery Data (Case study: Astan Ghods Razavi Great Farm)

Application of satellite imagery and remote sensing techniques in agriculture and other natural resources has been approved by many studies. In this study two ETM+ imagery data for May and September 2012 of Astan Ghods Razavi Great Farm were acquired to identify the boundaries of lands cultivated with different crops coverage and to create crops maps of that farm. . To classify the images, the supervised classification methods including Maximum Likelihood and artificial neural network were used. In order to compare the results of two applied classification methods, the same training and testing samples were used. To evaluate the accuracy of classification results, the produced map was compared with the ground control points extracted by GPS and local observations. Kappa coefficient and overall accuracy were estimated to be 82% and 85%, respectively by maximum likelihood method and these outputs were estimated to be 84% and 87%, respectively by neural network approach. The difference of cultivated area estimated by maximum likelihood and by neural network methods with actual measured area was 16.8% and 14.2%, respectively. The results of this study showed that satellite imagery has high capabilities to classify and estimate agricultural and cultivated areas. These data can be useful for strategic management to develop mechanization and cultivation plans

Performance Analysis of a Solar Dryer Equipped with a Recycling Air System and Desiccant Chamber

Drying is a high energy consuming process. Solar drying is one of the most popular methods for dehydration of agricultural products. In the present study, the performance of a forced convection solar dryer equipped with recycling air system and desiccant chamber was investigated. The solar dryer is comprised of solar collector, drying chamber, silica jell desiccant chamber, air ducts, fan and measuring and controlling system. Drying rate and energy consumption in three levels of air temperature (40, 45 and 50 oC) and two modes of drying (with recycling air and no-recycling with open duct system) were measured and compared. The results showed that increasing the drying air temperature decreased the drying time and increased the energy consumption in the mode of non-recycling air system. The dryer efficiency and drying rate were better in the mode of recycling air system than open duct system. The highest dryer efficiency was obtained from drying air temperature of 50 oC and the mode of recycling air system. In general, the efficiency of solar collector and the highest efficiency of the dryer were 0.34 and 0.41, respectively

Exploring and regression analysis of forces applied on Gastrocnemius muscle of drivers during clutching of MF 285 and MF 399 tractors : Ergonomic design approach

In this research the imposed force on Gastrocnemius muscle of the tractor driver during clutching has been studied. The number of sample people was assigned 30 and the research was conducted on MF285 and MF399 tractors. The clutching forces for these tractors were measured as 340 N and 290 N, respectively. The angle of knee location in these two tractors at 5 percent level was significantly different. The average decrease of pain threshold after 30 seconds and 60 seconds clutching and 60 seconds rest after clutching in MF285 tractor in Gastrocnemius muscle were more than MF399 tractor. The impact of BMI index Regression coefficient was found the highest among at all intervals during and after the clutching on both tractor drivers on decrease of pain threshold. It is suggested that in order to decrease the imposed force of clutching for MF285 tractor required modifications is performed. In this regard the force transfer joint between pedal and the disc in the mechanism of clutching can be made of cast iron.Keywords: ergonomic, tractor, operator, muscle, GastrocnemiusGodkänd; 2013; 20160804 (fahe